The GM of my guild is doing something really amazing next week, namely hosting a PvP pet battle tournament. One of the rules is that you must maintain the same team throughout, which of course places a premium on versatility.

Typically my go-to versatile team is Spring Rabbit/Valk/Crawdad. It's a bit cheesy but has good coverage against an array of comps. What do you guys think would be a good comp to run? As a backup, I may do Death Adder/Valk/Jademist, but I've had so-so luck overall with that team.

The first team you listed looks good. As you mentioned, its versatile - it will give you a chance to win every game. It also allows you to play from behind if things start off poorly. The Jademist team, on the other hand, seems fragile. Death Adder and Jademist both have low HP, and can be 2-shotted by a number of pets. You want a pet to be able to tank while Haunt is active.

your biggest con are birds I think - especially 1 raven or crow you can probably just forfeit :p

But try to think of other popular battlers, and think if you can win of them.

Say enemy valkyr: if you start with valkyr too, it's dangerous to use the haunt or you risk losing your valkyr.But you can soak with crawdad, it won't take too much damage. So let's say the enemy valkyr is dealt with if you make it dot crawdad.

anubis: dangerous pet. if your valkyr didn't face him initally. During sandstorm your haunt will only tick for about 70dmg on another pet. And anubis' demolish will probably crush your bunny and crawdad. (Rabbit can keep it busy, but it won't have the damage to take it down properly). But in the end valkyr should win over anubis. So anubis is okay, but dangerous if your valkyr isn't dealing with it.(All pets with demolish should be banned from the tournament because it's broken )

enemy crawdad: I'm not sure your pets can kill another crawdad. your valkyr is weak in damage. Your rabbit is probably super fast and low on damage + no dots...

healing teams in general are painful for your team (sunflower, ruby droplet,...): it will mainly depend on your valkyr, since that is the main source of damage. But valkyr is easily dealt with for them too. Sunflower easily outheals all the damage a valkyr can do. ruby droplet can skillfuly block the curse of doom.

moths: tough, I would say you lose if valkyr didn't damage it to get it below 50% asap (so rabbit can deal with it)

direhorns: If they have the shield ability, making haunt very weak I think you likely lose. Your rabbit will get 2-3shot and they outdamage crawdad's healing.

imp: not much trouble: weak dot on the rabbit. Easily outhealed/shielded by crawdad, valkyr is strong.

mechanicals with mines: highly annoying because you must swap in and out quite often with this team.

bone spider / crawling claw: curse of doom: since valkyr is probably "dead" it either ends up on your rabbit (which you can dodge when it's 2 rounds remaining, no issue) or on your crawdad, which is weak. Death grip isn't really an issue.

flayer youngling / scalded basilisk / vermling / hopper: Since your rabbit is faster than any of these I don't see a problem.if crawdad takes the shield ability this is also little issue for him.

Ragnaros: rabbit can handle it.

animus: with some good guessing and dodging/burrowing the heal, it should be no issue for rabbit.

aoe teams: since your valkyr is dead most of the time - so taking no damage - it should be okay

so now it's up to you to either think of a strategy against teams where I think you should lose. Or just gamble and accept you have a high chance of losing from those. In the end you will ALWAYS have weaknesses of course.

Personally I don't really like the crawdad playstyle. All the swapping involved, and slow killing. Your valkyr deals most of its damage while dead. Your rabbit is a master of dodging and burrowing. Do you really need that crawdad for heals ....But that's personal preference I'd replace crawdad with death adder or some anti-healing pet.

2 teams I use is for my weekly 10 battles is Ragnaros, Anubis idol and Lil bling. 2nd team is magical crawdad, valk and shore crab. This team works somewhat like a stall team as well and drives folks nuts. I think that's pretty cool what your guild is doing and good luck to you